<?phpclass HT_front_end{		public function __construct(){			add_image_size( 'slider_thumb',  590, 280, true ); 	}		public function show_slider(){			$slider = new wp_query( array( 'post_type'=>'post' ) );		if( $slider -> have_posts() ) : while( $slider->have_posts() ) : $slider->the_post();			?>			<li>				<a href="<?php the_permalink() ; ?>">				<?php 				if ( has_post_thumbnail() ) {					the_post_thumbnail( 'slider_thumb' );				}				else {					echo '<img src="' . get_bloginfo( 'template_directory' ) . '/images/thumbnail-default.jpg" />';				}				?></a>				<div class="some_info">					<h2 class="post_title"><a href="<?php the_permalink() ; ?>"><?php the_title() ; ?></a></h2>					<div class="short_content"><?php the_excerpt();?></div>				</div>			</li>			<?php					endwhile;		else : echo "Sorry.There are no post to display";		endif;	}	}?>